a large swath of the city would be impacted by a single shell. it's estimated 18,000 people would be killed in a day. let's get straight to cnn pentagon correspondent barbara starr. barbara, what have you learned tonight? >> well, you know, as tragic and serious as this is for the people of syria, this now has regional implications throughout the middle east. intelligence services from israel, turkey, jordan, lebanon, all the countries surrounding syria are now talking with the united states around the clock about this very scenario. because if there were to be, god forbid, a chemical attack, the concern is some of that could drift across boreder ed. worse, even as tragic as that would be, what if the regime collapses, terrorists move in, insurgent groups move in and grab some chemical material. they could take it across the borders into the neighbors countries and you would have a full-fledged crisis in the region. >> there has been talk that assad may try and seek asylum. what are you being told about that and the possibilities? >> you know, th